Most anti-bacterial soap contains triclosan.
Research published in the Proceedings of the National Academy of Sciences suggests that triclosan hinders human muscle contractions at the cellular level, as well as inhibiting muscle function in both fish and mice.
"Triclosan is found in virtually everyone's home and is pervasive in the environment. These findings provide strong evidence that the chemical is of concern to both human and environmental health."
The mice showed reductions in heart muscle function by as much as 25 percent, and a reduction of grip strength of 18 percent. The fish became less effective swimmers after exposure to triclosan.
source : http://www.pnas.org/content/early/2012/08/08/1211314109.abstract; http://blogs.smithsonianmag.com/science/2012/08/triclosan-a-chemical-used-in-antibacterial-soaps-is-found-to-impair-muscle-function/
